Active Oxygen Species in La_n+1Ni_nO_3n+1 Layered Perovskites for Catalytic Oxidation of Toluene and Methane

Abstract

Layered perovskites possess frameworks that can sustain a larger extent of oxygen nonstoichiometry than perovskites, which makes them possibly more suitable for catalytic applications. However, there is little work in literature concerning the catalytic behaviors of them. In this paper, La n+1Ni n O3n+1 layered perovskites were selected as potential catalysts for catalytic oxidation of toluene and methane. The activation and transmission of active oxygen species over the layered structure were explored by using a range of analytical techniques, e.g., O2-TPD, XPS, and H2-TPR. It was noted that the LaNiO3 (n = ∞) that possessed the most chemisorbed oxygen species had the lowest activation energy (E a, ca. 70.1 kJ mol–1) in toluene oxidation and the La4Ni3O10 (n = 3) that owned a superior lattice oxygen mobility showed the lowest E a (ca. 111.0 kJ mol–1) in methane oxidation. The La2NiO4 (n = 1) that lacked chemisorbed and superficial lattice oxygen species yielded the highest E a in either toluene or methane oxidation. It is expected that the work conduct herein could generate more awareness onto the potential catalyst application for layered perovskites and would also give promising insights into the correlation between structural framework and catalytic behaviors for extraordinary materials.

Factors Controlling the Redox Activity of Oxygen in Perovskites: From Theory to Application for Catalytic Reactions

“…From both desorption and spectroscopic measurements, it was thus concluded that α-O was surface adsorbed oxygen while β-O was lattice oxygen. Building upon these early works, the complexity of these oxygens were further uncovered and their dependence on the chemistry of the perovskites thoroughly discussed [103][104][105][106].…”

Barium- and Strontium-Containing Anode Materials toward Ceria-Based Solid Oxide Fuel Cells with High Open Circuit Voltages

“…High-resolution O 1s spectra of SDC, SDC-BS91, and BSZCY91 can be fitted with four peaks (Figure 6d). The peaks centered at ~528.7, ~530.3, ~531.2 and ~532.3 eV are attributed to the lattice oxygen species O 2-, reactive oxygen species, chemisorbed H2O or CO3 2-, and -OHor O 2 , respectively [30][31][32] . Compared to SDC, SDC-BS91 shows a significantly enhanced peak corresponding to chemisorbed H2O or CO3 2-, which is similar to that of BSZCY91.…”

Kinetics of photocatalytic degradation of gaseous p‐xylene on UiO‐66‐NH2 and LaFeO3 thin films under combined illumination of ultraviolet and visible lights

“…To date, although TiO 2 ‐based materials are most studied as photocatalysts, other semiconductors are also increasingly concerned for this purpose. Among the groups of metal oxides studied, perovskite‐based catalysts have been confirmed to be effective in catalytic, energy, and environmental applications …”

“…Among the groups of metal oxides studied, perovskite-based catalysts have been confirmed to be effective in catalytic, energy, and environmental applications. 6 Perovskites are groups of compounds with the formula ABO 3 , whose crystal structure provides a large opportunity to adjust the absorption of light to the visible region and band gap energy in accordance with specific photocatalytic reactions, having unique photochemical properties, and offer distinct advantages. 7 For example, most titanate perovskites have band gap energy (E g ) greater than 3.0 eV and show good photocatalytic activity under UV radiation.…”